This study aims to investigate the clinical role of preoperative pyuria for predicting bacillus Calmette-Guérin (BCG) unresponsiveness in non-muscle invasive bladder cancer (NMIBC). We performed a logistic regression analysis on 453 patients with NMIBC who were treated with BCG immunotherapy after a transurethral resection of bladder tumours, to evaluate predictive factors of BCG unresponsiveness. We also analysed univariate and multivariable survival data to estimate the prognostic impact of pyuria. Of the total study population, 37.6% (170/453) of patients had BCG unresponsiveness. A multivariable logistic regression analysis revealed that a history of upper urinary tract cancer (odds ratio (OR): 1.86, 95% confidence interval (CI): 1.04-3.32, p-value = 0.035) and the presence of pyuria (OR: 1.51, 95% CI: 1.01-2.27, p = 0.047) and tumour multiplicity (OR: 1.80, 95% CI: 1.18-2.75, p-value < 0.001) were significant predictors of BCG unresponsiveness. A Cox proportional hazards analysis model showed that pyuria was a significant prognostic factor for progression-free survival (hazard ratio: 4.51, 95% CI: 1.22-16.66, p = 0.024). A history of upper urinary tract cancer and the presence of pyuria and tumour multiplicity are predictive markers of BCG unresponsiveness. For patients with NMIBC who have preoperative pyuria, treatment using BCG should be considered cautiously.
Keywords: BCG immunotherapy; non-muscle invasive bladder cancer; pyuria.